title: Development of a beveled fiber-optic confocal Raman probe for enhancing in vivo epithelial tissue Raman measurements at endoscopy.
abstract: We report on the development of a beveled fiber-optic confocal Raman probe coupled with a ball lens for enhancing in vivo epithelial tissue Raman measurements at endoscopy. Our Monte Carlo simulations show that by selecting a proper fiber-ball lens distance and beveled angle of collection fibers, the confocal Raman probe design can be optimized for maximizing shallower tissue Raman measurements in epithelial tissue; in addition, the ratio of epithelium to stromal Raman photons collected using an optimized confocal Raman probe is approximately 19-fold higher than that using a volume-type Raman probe. Further experiments confirm that the confocal Raman endoscopic probe developed is in favor of probing superficial tissue Raman signals from a two-layer tissue phantom as well as esophagus tissue in vivo during endoscopy. This work suggests the great potential of applying the beveled fiber-optic confocal Raman probe for improving in vivo diagnosis of precancer occurring in epithelial tissue at endoscopy.
authors.affiliation: Optical Bioimaging Laboratory, Department of Bioengineering, Faculty of Engineering, National University of Singapore, Singapore 117576.
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Wang
authors.forename: Mads Sylvest
authors.initials: MS
authors.lastname: Bergholt
authors.forename: Wei
authors.initials: W
authors.lastname: Zheng
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Huang
mesh_terms: D004724:Endoscopy / Q000295:instrumentation*; D004848:Epithelium / Q000378:metabolism; D004947:Esophagus / Q000166:cytology; D009010:Monte Carlo Method; D055100:Optical Fibers; D013059:Spectrum Analysis, Raman / Q000295:instrumentation*